Question: $\dfrac{8}{10} - \dfrac{3}{8} = {?}$
Explanation: $ = {\dfrac{8 \times 4}{10 \times 4}} - {\dfrac{3 \times 5}{8 \times 5}} $ $ = {\dfrac{32}{40}} - {\dfrac{15}{40}} $ $ = \dfrac{{32} - {15}}{40} $ $ = \dfrac{17}{40}$